Piano-lock.



H. J. STRONG & S. OSTRANDER.

PIANO LOOK.

APPLICATION FILED FEB. 15, 1912. I 1,040,963, Patented 0ct.8, 1912.

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UNITED STATES PATENT OFFICE.-

I-IARRY J'. STRONG AND SHERIDAN OSTRANDER, OF CHICAGO, ILLINOIS; SAID OS'IRANDER ASSIGNOR TO SAID STRONG.

PIANO-LOCK.

Specification of Letters Patent.

Patented Oct. 8,1912.

To all whom it may concem:

Be it known that we, HARRY J. STRONG and SHERIDAN OSTRANDER, citizens of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Piano-Locks, of which the following is a specification.

This invention relates to improvements in looks and especially in the style of locks adapted for use in pianos.

In the locks almost universally used for pianos the lock case is rectangular in form and is set into a mortise cut in the lock slip of the piano so that the face plate of the lock is flush with the upper edge of the lock slip and a second mortise or opening is cut at right angles with the lock receiving mortise to permit the insertion of the key which operates the lock bolt. The bolt is usually shaped at its outer end and engages a strikeplate set in the lower edge of the fall-board. Owing to the necessity of making the lock attenuated in order to fit between the sides of the comparatively thin boards which form the fall-board and lock slip members, the ordinary locks are more or less fragile. Furthermore the necessity of reaching said looks from an opening cut from the outer face of the lock slip in addition to the expense of setting the lock causes defacement to the otherwise highly polished surface of the lock slip member. A further objection to the common style of piano locks is that the vertical movement of the bolt parts is so limited that if the fall-board or look slip should balk slightly it would be difiicult to move the bolt into locking position in the strike or bolt receiving plate.

The especial object of our invention is to provide a lock which can be manufactured with great economy which can be applied to a piano by unskilled labor and without defacing the front of the lock slip as no key opening is required extending transversely to the recess in which our improved lock is inserted.

In the accompanying drawing which forms a part of this application, we have illustrated our improved lock in connection with the portions of the piano to which the lock members are ordinarily attached in the following views.

Figure 1 is a sectional view taken through a portion of the fall-board the lock slip and key bottom of a piano frame the lock members being shown in elevation in their locked position; Fig. 2 is a bottom plan view' which is secured the key bottom piece 6 and above the lock slip section is shown a sectional view of the portion of the fall board of the piano cover.

To the upper edge of the lock slip are secured rubber buttons 5 upon which rest the lower edge of the fall board when the piano is in its closed position. Extending vertically through the lock slip is a cylindrical opening 5 which registers with a similar opening extending through the key bottom member. the fall board inwardly for a short distance is a circular recess 7*. Inserted in the lower end of the cylindrical opening in the key bottom 6 is a collar 8 which is secured in place by close frictional engagement with the walls of the cylindrical opening in which it is placed and serves as a key receiving escutcheon. Similarly secured in the upper end of the cylindrical opening 5 is a socket plate 9 formed with a transversely extending rectangular recess 9 in its upper portion and with a circular rim or flange surrounding and overhanging the adjacent edges of the opening 5*. Through the bottom of the socket member 9 is a hole which receives with a sliding fit a bolt 10 consisting of a cylindrical rod of suitable material having on one end a rectangular head 10 somewhat longer than it is wide and on the opposite end is secured a cylindrical piece 10 in which is formed an open notch 10 adapted to receive the end 13 of the key 13 having on its opposite end a thumb piece or handle 13. Surrounding the bolt 10 is an expansion coil spring 11 which is secured at its upper end to a washer 11 which surrounds the bolt and is attached to the under side of the socket 9. The lower end of the spring 11 bears against the inner end of the cylindrical piece 10". The strike plate or bolt Extending from the lower edge of i receiving member consists merely of a flat plate 12 having an elongated rectangular opening 12 which registers with the recess 7 in the fall-hoard. This plate is secured to the lower edge of the fall-board 7 by screws 12*. The opening 12 is so propor tioned as to easily receive the bolt head 10 and when the latter passes through said opening into the recess 7 it is given a quarter turn and'thereby engages the edges of the plate 12 thus locking the fall-board to the lock slip. The bolt is operated by inserting the tang 13 of the key 13 in the slot 10 and pushing the key upwardly so as to compress the spring 11 and thereby project the bolt 10 upwardly through the opening 12 into the recess 7 The key is then given a square turn which brings the bolt 10 transversely to the opening 1%.

From the construction and operation described, it will be obvious that the projection of the bolt is limited only to the compressibility of the spring 11 and in practice this spring will be so proportioned to the other parts of the look as to permit a relatively great projection of the bolt and thus take care of any warping or bad fit of the fall board to the lock slip.

It is also apparent that our improved lock can be attached by merely boring a cylindrical opening through the lock slip and key bottom with an ordinary circular bit and that the recess 7 may be formed with the same tool. The only screws required in this connection are those securing the plate 12 to the fall-board.

Having thus described our invention what we claim as new, is

1. A look comprising a socket plate having an elongated rectangular recess in its outer face, a bolt slidably mounted in said plate and having a head fitting said recess and having secured to its opposite end, a

key engaging member provided with a recess, an expansion coil spring arranged between the said socket member and said key receiving member and adapted to normally hold the bolt head in said recess, in, combination with a strike plate having an opening adapted to engage said bolt head when the latter is projected from said socket member, said bolt adapted to be projected and to be rotated by a suitable key engaging said key receiving member.

2. A look comprising a circular socketplate having an elongated recess in itsggg outer face, a bolt slidably mounted in said gjplate, having on one end a head adapted to be seated in said recess, and on its opposite end a slotted block, a spring surrounding said bolt and bearing against said socketplate and block, a strike-plate having an opening adapted to engage said bolt head, and a key adapted to engage said slotted block to rotate and project said bolt.

In testimony whereof we affix our signatures in the presence of two witnesses.

HARRY J. STRONG. SHERIDAN OSTRANDER. Witnesses:

F. BENJAMIN, M. A. MILORD.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. G. 

